With rapid development of Internet technology, social network service (SNS) has also been rapidly developed. Relationship chain is important in SNS. For example, relationship between users, user-generated content (UGC) via Internet, user forwarding, comments, user-interested content, and/or interactions between users in SNSs are often based on the relationship chain as for spread and dissemination. Development and maintenance of the relationship chain are therefore very crucial.
In existing SNS technology, expansion of relationship chain and friend recommendation may use common relationship between two people to find some overlaps including, public city, common school, same company, mutual friend, and other factors, used to determine whether to extend the relationship chain, or whether there is a need to recommend a friend. However, evaluation of a weight value of these factors is often empirically identified and artificially configured. Consequently, the configuration of weight value is fixed, which does not facilitate accurate expansion of the relationship chain for the user.